(In [15144]) Fixed #11434 -- Corrected style of arrow buttons located at the center of filter_{horizontal|vertical} m2m widgets to not give them focus borders that span from the left page border. Thanks defaultwombat for the report and patch.

(In [15181]) [1.2.X] Fixed #11434 -- Corrected style of arrow buttons located at the center of filter_{horizontal|vertical} m2m widgets to not give them focus borders that span from the left page border. Thanks defaultwombat for the report and patch.